This invention relates to a catheter and a method for making the same.
When a catheter is inserted into a blood vessel or other body cavity, it is guided in with a guide or deflector wire. The catheter can be advanced to a destined location for medical treatment or diagnosis while controlling the direction of the catheter tip.
The body portion of such a catheter must have a certain degree of rigidity or relatively low flexibility while the tip portion must have a certain degree of softness or a relatively high flexibility and sometimes be plastically deformable to permit bending to a desired shape. In particular, intravascular catheters which are inserted and advanced into blood vessels must have a tip portion with a relatively high flexibility to prevent the catheter from damaging the inner wall of the vessel. At the same time, the body portion must have a relatively low flexibility to allow the force used to advance the catheter to be properly transmitted to the tip portion. In some cases, the tip portion of the catheter must be plastically deformable to permit bending to ensure proper insertion of the catheter in different cavities and areas of the body, which often differ considerably in shape from patient to patient.